Provided is an electronic device comprising a front cover; a rear cover facing in a direction opposite to that of the front cover; and a side frame enclosing a space between the front cover and the rear cover, a side frame at least partially forming an external shape of the electronic device, the side frame comprising conductive material; a support at least partially extended from the side frame to the space, the support comprising conductive material; and a polymer member coupled to at least a portion of the support or the side frame, wherein the polymer member comprises a first area in which an adhesive member for attachment of the front cover or the rear cover is disposed and a second area extended from the first area and contacting the side frame.